Freertos tick issue on nRF52. Can lead to lockups. SDK11

[Anders Strand]

The tick count update in tickless idle mode is only executed when the rtos tick handler is executed. If different interrupt wakes up the CPU, the tick count is invalid. This may in some cases lead to the cpu sleeping for the maximum RTC clock time. It will be experienced as a lockup. This will be fixed in the next SDK release (current is SDK 11.0)

Threads describing the issue:

• FreeRTOS tick count invalid when using tickless idle

• Tickless overrun issue using FreeRTOS, nRF52

The FIX: Replace the following two files in the SDK folder, with the files attached in this post.

• \external\freertos\config\FreeRTOSConfig.h
• \external\freertos\portable\CMSIS\nrf52\port_cmsis_systick.c

Fixed files:

• FreeRTOSConfig.h

• port_cmsis_systick.c

[WestCoastDaz]

Anders,

I have implemented the fixes you included in this post and our FreeRTOS implementation and we are still missing ticks which is causing our system to lose time. Any ideas on how to correct this?

[Anders Strand]

Thanks for reporting, i will look into it.

[jules]

Hi, I'm trying to reset a software timer with an external irq. When not using tickless idle, this works fine. When I turn tickless idle on however, the timer is not properly reset, even after using SDK 12.1. Is this still a bug in the Freertos port or am I doing something wrong here?

[Susheel Nuguru]

Please open a new thread and upload your project. I will take a look at it. Hard to say if it is a bug or not without looking at the code and the sequence.

[jules]

Hi Aryan,

I opened a new thread, will you please have a look at it? Thank you very much! devzone.nordicsemi.com/.../